1 files changed, 85 insertions, 38 deletions

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index daf7b4659b4a..94747afc2e78 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -2872,56 +2872,55 @@ static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data)
 }
 
 /*
- * Request sync osd watch/unwatch.  The value of "start" determines
- * whether a watch request is being initiated or torn down.
+ * Initiate a watch request, synchronously.
  */
-static int __rbd_dev_header_watch_sync(struct rbd_device *rbd_dev, bool start)
+static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev)
 {
 	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
 	struct rbd_obj_request *obj_request;
 	int ret;
 
-	rbd_assert(start ^ !!rbd_dev->watch_event);
-	rbd_assert(start ^ !!rbd_dev->watch_request);
+	rbd_assert(!rbd_dev->watch_event);
+	rbd_assert(!rbd_dev->watch_request);
 
-	if (start) {
-		ret = ceph_osdc_create_event(osdc, rbd_watch_cb, rbd_dev,
-						&rbd_dev->watch_event);
-		if (ret < 0)
-			return ret;
-		rbd_assert(rbd_dev->watch_event != NULL);
-	}
+	ret = ceph_osdc_create_event(osdc, rbd_watch_cb, rbd_dev,
+				     &rbd_dev->watch_event);
+	if (ret < 0)
+		return ret;
+
+	rbd_assert(rbd_dev->watch_event);
 
-	ret = -ENOMEM;
 	obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
-							OBJ_REQUEST_NODATA);
-	if (!obj_request)
+					     OBJ_REQUEST_NODATA);
+	if (!obj_request) {
+		ret = -ENOMEM;
 		goto out_cancel;
+	}
 
 	obj_request->osd_req = rbd_osd_req_create(rbd_dev, true, 1,
 						  obj_request);
-	if (!obj_request->osd_req)
-		goto out_cancel;
+	if (!obj_request->osd_req) {
+		ret = -ENOMEM;
+		goto out_put;
+	}
 
-	if (start)
-		ceph_osdc_set_request_linger(osdc, obj_request->osd_req);
-	else
-		ceph_osdc_unregister_linger_request(osdc,
-					rbd_dev->watch_request->osd_req);
+	ceph_osdc_set_request_linger(osdc, obj_request->osd_req);
 
 	osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_WATCH,
-				rbd_dev->watch_event->cookie, 0, start ? 1 : 0);
+			      rbd_dev->watch_event->cookie, 0, 1);
 	rbd_osd_req_format_write(obj_request);
 
 	ret = rbd_obj_request_submit(osdc, obj_request);
 	if (ret)
-		goto out_cancel;
+		goto out_linger;
+
 	ret = rbd_obj_request_wait(obj_request);
 	if (ret)
-		goto out_cancel;
+		goto out_linger;
+
 	ret = obj_request->result;
 	if (ret)
-		goto out_cancel;
+		goto out_linger;
 
 	/*
 	 * A watch request is set to linger, so the underlying osd
@@ -2931,36 +2930,84 @@ static int __rbd_dev_header_watch_sync(struct rbd_device *rbd_dev, bool start)
 	 * it.  We'll drop that reference (below) after we've
 	 * unregistered it.
 	 */
-	if (start) {
-		rbd_dev->watch_request = obj_request;
+	rbd_dev->watch_request = obj_request;
 
-		return 0;
+	return 0;
+
+out_linger:
+	ceph_osdc_unregister_linger_request(osdc, obj_request->osd_req);
+out_put:
+	rbd_obj_request_put(obj_request);
+out_cancel:
+	ceph_osdc_cancel_event(rbd_dev->watch_event);
+	rbd_dev->watch_event = NULL;
+
+	return ret;
+}
+
+/*
+ * Tear down a watch request, synchronously.
+ */
+static int __rbd_dev_header_unwatch_sync(struct rbd_device *rbd_dev)
+{
+	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
+	struct rbd_obj_request *obj_request;
+	int ret;
+
+	rbd_assert(rbd_dev->watch_event);
+	rbd_assert(rbd_dev->watch_request);
+
+	obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
+					     OBJ_REQUEST_NODATA);
+	if (!obj_request) {
+		ret = -ENOMEM;
+		goto out_cancel;
 	}
 
+	obj_request->osd_req = rbd_osd_req_create(rbd_dev, true, 1,
+						  obj_request);
+	if (!obj_request->osd_req) {
+		ret = -ENOMEM;
+		goto out_put;
+	}
+
+	osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_WATCH,
+			      rbd_dev->watch_event->cookie, 0, 0);
+	rbd_osd_req_format_write(obj_request);
+
+	ret = rbd_obj_request_submit(osdc, obj_request);
+	if (ret)
+		goto out_put;
+
+	ret = rbd_obj_request_wait(obj_request);
+	if (ret)
+		goto out_put;
+
+	ret = obj_request->result;
+	if (ret)
+		goto out_put;
+
 	/* We have successfully torn down the watch request */
 
+	ceph_osdc_unregister_linger_request(osdc,
+					    rbd_dev->watch_request->osd_req);
 	rbd_obj_request_put(rbd_dev->watch_request);
 	rbd_dev->watch_request = NULL;
+
+out_put:
+	rbd_obj_request_put(obj_request);
 out_cancel:
-	/* Cancel the event if we're tearing down, or on error */
 	ceph_osdc_cancel_event(rbd_dev->watch_event);
 	rbd_dev->watch_event = NULL;
-	if (obj_request)
-		rbd_obj_request_put(obj_request);
 
 	return ret;
 }
 
-static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev)
-{
-	return __rbd_dev_header_watch_sync(rbd_dev, true);
-}
-
 static void rbd_dev_header_unwatch_sync(struct rbd_device *rbd_dev)
 {
 	int ret;
 
-	ret = __rbd_dev_header_watch_sync(rbd_dev, false);
+	ret = __rbd_dev_header_unwatch_sync(rbd_dev);
 	if (ret) {
 		rbd_warn(rbd_dev, "unable to tear down watch request: %d\n",
 			 ret);